Sleeve terminals provide an electrical connection with a pin terminal which is concentrically received by a slotted sleeve member of the sleeve terminal, where in the sleeve member is resiliently expanded by the pin terminal and presses thereagainst. A typical example of a sleeve and pin terminals connection is that of a spark plug wire sleeve terminal which receives therein the pin terminal at the top of a spark plug.
An interesting example of a sleeve terminal is presented in U.S. Pat. No. 5,775,960, and is generally reproduced at FIGS. 1 and 2. As shown at FIG. 1, a sleeve terminal 10 is composed of a pair of opposed resilient arms 12, 14 which are connected to a base 16, which is, in turn, connected to a wire mount 18. The resilient arms 12, 14 are separated from each other by slits 20, 22, and each feature a forward flaired end 24, 26 (which collectively form what is basically a sleeve member of the sleeve terminal). The resilient arms 1214 are inserted into a barrel 28 having an access opening 30. As shown at FIG. 2, a pin terminal 32 is then inserted through the access opening 30 and between the resilient arms 12, 14, causing them to deflect away from each other as they resiliently press against the pin terminal.
While a sleeve terminal does offer a good electrical connection with a received pin terminal, there is a danger that the sleeve member may relax and no longer provide a secure normal force against the pin terminal. If the sleeve member should loose good abutting contact with the pin terminal, the electrical connection therebetween is then compromised. Unfortunately, over time due to vibration and heat, among other things, the sleeve member can relax, whereby the normal force of the sleeve member against the pin terminal reduces commensurately. Accordingly, it is seen that when the normal force of the sleeve member decreases, there is introduced potential loss of electrical continuity between the sleeve terminal and the received pin terminal.
Accordingly, what remains needed in the art is a sleeve terminal which provides an assured level of normal force with respect to a received pin terminal, besides providing a ground plane to an internal wall of a barrel shaped shield.